Valuation And Qualifying Accounts And Reserves (Schedule Of Valuation And Qualifying Accounts) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
SEC Schedule, 12-09, Allowance, Credit Loss
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Balance at Beginning of Year	$ 199	$ 122	$ 100
Additions	6	88	32
Deductions	(28)	(12)	(28)
Balance at End of Year	215	199	122
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount	215	199	122
Additions	6	88	32
SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction	28	12	28
SEC Schedule, 12-09, Valuation Allowances and Reserves, Increase (Decrease) Adjustment	38	1	18
SEC Schedule, 12-09, Valuation Allowances and Reserves, Increase (Decrease) Adjustment	38	1	18
SEC Schedule, 12-09, Valuation Allowance, Deferred Tax Asset
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Balance at Beginning of Year	209	281	339
Additions	58	18	7
Deductions	(51)	(90)	(65)
Balance at End of Year	216	209	281
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount	216	209	281
Additions	58	18	7
SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction	51	90	65
SEC Schedule, 12-09, Valuation Allowances and Reserves, Increase (Decrease) Adjustment	0	0	0
SEC Schedule, 12-09, Valuation Allowances and Reserves, Increase (Decrease) Adjustment	$ 0	$ 0	$ 0